Puerto Rican/American Bermudez began wrestling in 2000 and held a high school record of 112 wins and 23 losses.[6] From high school he went on to wrestle at Bloomsburg University of Pennsylvania where in 2007 he was ranked 22nd in the nation at the Division 1 level. Bermudez then became a college free-style All-American in Akron, Ohio.[7]

Bermudez first started training mixed martial arts in Saugerties, New York, his home town, in 2009. He later went on to train at Blackman MMA in Harrisburg, Pennsylvania. He trained at Blackman MMA for nearly two years as he competed as an amateur and professional. Bermudez competed in four amateur bouts before earning his professional license, finishing his amateur career with four wins and no losses.[6] He began his pro career in 2009, opening his career with a record of 4-0, all four won via stoppage. The wins earned him a fight for Russian promotion, M-1 Global. The fight was held at the event M-1 Selection 2010 in New Jersey against Kevin Roddy. Bermudez controlled the entirety of the fight and won via unanimous decision. He was not selected to compete in the M-1 Global tournament, and never returned to fight for the promotion.

Bermudez returned to Pennsylvania Fighting Championships for one fight before signing with Shine Fights. Bermudez signed onto compete in Shine Fights 2010 Lightweight Grand Prix. His first fight in the tournament was against UFC veteran Shannon Gugerty. Bermudez won the fight via unanimous decision and moved onto fight UFC, MFC, Strikeforce, and DREAM veteran, Drew Fickett. Fickett handed Bermudez his first loss, submitting him in the first round via rear naked choke. He lost his second straight fight, also via rear naked choke, to undefeated Jordan Rinaldi. After the losses, Bermudez showed interest in dropping weight classes to compete at featherweight.

Bermudez was selected to be a part of Team Mayhem as the team's first pick (second overall). In his quarterfinal bout, Bermudez fought Stephen Bass. Bermudez controlled the fight throughout round one before winning the fight in the second round via TKO.

Bermudez was selected to fight Team Bisping member Akira Corassani in the semi-finals. After being knocked down twice, Bermudez took Corassani down and finished the fight in the first round via submission due to a guillotine choke. With the win, Bermudez moved into the finals set to take place at The Ultimate Fighter 14 Finale. The submission also won Bermudez an additional $25,000 for the fan voted "Submission of the Season".

Bermudez officially made his UFC debut on December 3, 2011 at The Ultimate Fighter 14 Finale against Diego Brandão to determine the winner of The Ultimate Fighter 14. After a back-and-forth first round Bermudez knocked down Brandão and displayed strong ground and pound from the top position but while doing so Bermudez was caught in an armbar that ended the fight. The bout earned Fight of the Night honors, giving Bermudez an extra $40,000 in bonuses.

Bermudez fought Tommy Hayden on August 11, 2012 at UFC 150.[9] Bermudez won late into round one after clipping Hayden with a front kick to the chest, a straight right to the face then catching him in a guillotine choke, causing Hayden to submit. The performance earned Bermudez Submission of the Night honors.

Bermudez next faced Matt Grice on February 23, 2013 at UFC 157.[10] Bermudez won via split decision (29-28, 28-29, 29-28). The back and forth action earned both fighters Fight of the Night honors and much praise from MMA observers proclaiming it was an early front runner for "Fight of the Year".[11]

Bermudez next faced Jimy Hettes on March 15, 2014 at UFC 171. He won the fight via TKO in the third round and won his first Performance of the Night bonus award.[16]

In his highest profile fight to date, Bermudez faced Clay Guida on July 26, 2014 at UFC on Fox 12.[17] He won the bout via submission in the second round, and earned a Performance of the Night bonus award for the second time in a row.[18]